How to get search bar to work in a uicollectionview

Question

I want to place a search bar above a uicollection view like the image below. I want to do this programmatically.

current view

This is my code for search bar setup function. I have it in the home view controller.

func setupSearchBar() {

    let searchBar = UISearchBar(frame: CGRect(x: 0, y: 64, width:UIScreen.main.bounds.width, height: 32))
    searchBar.barTintColor = UIColor(red: 64/255, green: 64/255, blue: 64/255, alpha: 1)
    searchBar.backgroundColor = UIColor.blue
    searchBar.isTranslucent = true
    searchBar.placeholder = "Search Timeline"
    searchBar.searchBarStyle = UISearchBarStyle.prominent
    view.addSubview(searchBar)

} 

Answer 1

You can add the search bar to your UICollectionview header.

This creates the searchBar programmatically

    lazy var searchBar : UISearchBar = {
    let s = UISearchBar()
        s.placeholder = "Search Timeline"
        s.delegate = self
        s.tintColor = .white
        s.barTintColor = // color you like
        s.barStyle = .default
        s.sizeToFit()
    return s
}()

Next, in your view did load register the header view.

collectionView?.register(UICollectionViewCell.self, forSupplementaryViewOfKind: UICollectionElementKindSectionHeader, withReuseIdentifier: "headerCellId")

Override the below method to define the height you would like your header to be.

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForHeaderInSection section: Int) -> CGSize {
    return CGSize(width: view.frame.width, height: 40)
}

Last, add search bar to UICollectionview header, defining the constraints to fit the entire header view.

    override func collectionView(_ collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, at indexPath: IndexPath) -> UICollectionReusableView {
    let header = collectionView.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: "headerCellId", for: indexPath)
        header.addSubview(searchBar)
        searchBar.translatesAutoresizingMaskIntoConstraints = false
        searchBar.leftAnchor.constraint(equalTo: header.leftAnchor).isActive = true
        searchBar.rightAnchor.constraint(equalTo: header.rightAnchor).isActive = true
        searchBar.topAnchor.constraint(equalTo: header.topAnchor).isActive = true
        searchBar.bottomAnchor.constraint(equalTo: header.bottomAnchor).isActive = true
    return header
}

Answer 2

Try to add these code:

    // Call sizeToFit() on the search bar so it fits nicely in the UIView
    self.searchController!.searchBar.sizeToFit()
    // For some reason, the search bar will extend outside the view to the left after calling sizeToFit. This next line corrects this.
    self.searchController!.searchBar.frame.size.width = self.collectionView!.frame.size.width